DVI to VGA for Desktop LCD...& Faster External Hard Drives..?

I think the hardest part about Apple is deciding which Mac to get! Ever since the Mini was announced, I have been wanting to buy a Mac and dabble in the lightside

I’ve dismissed the Mini because I rather spend more on a faster, more featured Mac. I’ve been looking at the iMac G5 20”, Powermac 1.8Ghz (Single), and now Powerbook 15”.

My question about the Powerbook is could I use an adapter (DVI to VGA) to use my NEC 17” LCD monitor for desktop use? Or, do I have to have a DVI LCD monitor?

My main use for my Mac will be Photoshop CS, DVD ripping to DVD-R media, and general computing (Internet, word processing etc). Would an external DVD-R burner be better than upgrading to a SuperDrive?

Also, how is that an external hard drive with a faster rpm (72,000rpm) plugged into a firewire port will make your computer faster? I read that some Mac mini users where doing this to increase there mini’s performance compared to the slow 42,000rpm drives installed inside of them. Do they install there OS on the external hard drive?

An external dvd burner will probably be less expensive and probably faster than the built in superdrive. SuperDrives in iMacs and PowerBooks aren't as fast as the PowerMac because they are thinner and less powerful than the standard Internal DVD Burners.

Not sure about the External Hard Drive but I am assuming it is because it can write and read data faster than the built in drive